AS3 Scale9Grid ---- 9宫格类

源码：

/*****************************************************
 *  
 *  The Initial Developer of the Original Code is Jave.Lin(afeng).
 *  
 *  Scale9Grid.as
 *  Create By Jave.Lin(afeng)
 *  2012-9-5 下午2:37:14
 *  
 *****************************************************/
package testScale9Grid
{
	import flash.display.Bitmap;
	import flash.display.BitmapData;
	import flash.display.Sprite;
	import flash.events.Event;
	import flash.geom.Point;
	import flash.geom.Rectangle;
	
	/**
	 *  9宫格类
	 * @author Jave.Lin(afeng)
	 **/
	public class Scale9Grid extends Sprite
	{
		private var _invalidate:Boolean=false;
		private const despoint:Point=new Point();
		
		private var _top_left_bmp:Bitmap;
		private var _top_bmp:Bitmap;
		private var _top_right_bmp:Bitmap;
		private var _right_bmp:Bitmap;
		private var _bottom_right_bmp:Bitmap;
		private var _bottom_bmp:Bitmap;
		private var _botton_left_bmp:Bitmap;
		private var _left_bmp:Bitmap;
		private var _center_bmp:Bitmap;
		
		private var _s9d:Rectangle;
		
		private var _bmd:BitmapData;
		public function get bmd():BitmapData
		{
			return _bmd;
		}
		
		private var _w:Number;
		private var _minW:Number;
		public override function get width():Number
		{
			return _w;
		}
		public override function set width(value:Number):void
		{
			if(_w!=value)
			{
				_w=value;
				
				if(_w<_minW)_w=_minW;
				invalidate();
			}
		}
		
		private var _h:Number;
		private var _minH:Number;
		public override function get height():Number
		{
			return _h;
		}
		public override function set height(value:Number):void
		{
			if(_h!=value)
			{
				_h=value;
				if(_h<_minH)_h=_minH;
				invalidate();
			}
		}
		
		public function Scale9Grid(bmd:BitmapData,s9d:Rectangle)
		{
			super();
			
			_bmd=bmd;
			_w=bmd.width;
			_h=bmd.height;
			
			checkS9d(s9d);
			_s9d=s9d;
			
			_minW=(_s9d.x+(_bmd.width-_s9d.right)+1);
			_minH=(_s9d.y+(_bmd.height-_s9d.bottom)+1);
			
			cutBmd();
			refresh();
		}
		
		public function invalidate():void
		{
			_invalidate=true;
			removeEventListener(Event.RENDER,onRender);
			addEventListener(Event.RENDER,onRender);
		}
		
		public function refresh():void
		{
			_invalidate=false;
			refreshSize();
			layoutBmps();
//			graphics.clear();
//			drawRect(0xff0000,_top_left_bmp.getRect(this));
//			drawRect(0xff0000,_top_bmp.getRect(this));
//			drawRect(0xff0000,_top_right_bmp.getRect(this));
//			drawRect(0xff0000,_right_bmp.getRect(this));
//			drawRect(0xff0000,_bottom_right_bmp.getRect(this));
//			drawRect(0xff0000,_bottom_bmp.getRect(this));
//			drawRect(0xff0000,_botton_left_bmp.getRect(this));
//			drawRect(0xff0000,_left_bmp.getRect(this));
//			drawRect(0xff0000,_center_bmp.getRect(this));
		}
		
		private function onRender(event:Event):void
		{
			// TODO Auto-generated method stub
			if(!_invalidate)return;
			
			removeEventListener(Event.RENDER,onRender);
			
			refresh();
		}
		
		private function layoutBmps():void
		{
			//0、中
			_center_bmp.x=_s9d.x;
			_center_bmp.y=_s9d.y;
			var centerRect:Rectangle=_center_bmp.getRect(this);
			
			//1、左上
			_top_left_bmp.x=0;
			_top_left_bmp.y=0;
			
			//2、上
			_top_bmp.x=_s9d.x;
			_top_bmp.y=0;
			
			//3、右上
			_top_right_bmp.x=centerRect.right;
			_top_right_bmp.y=0;
			
			//4、右
			
			_right_bmp.x=centerRect.right;
			_right_bmp.y=_s9d.y;
			
			//5、右下
			_bottom_right_bmp.x=centerRect.right;
			_bottom_right_bmp.y=centerRect.bottom;
			
			//6、下
			_bottom_bmp.x=_s9d.x;
			_bottom_bmp.y=centerRect.bottom;
			
			//7、左下
			_botton_left_bmp.x=0;
			_botton_left_bmp.y=centerRect.bottom;
			
			//8、左
			_left_bmp.x=0;
			_left_bmp.y=_s9d.y;
		}
		
		private function refreshSize():void
		{
			var tw:Number=_w-(_left_bmp.width+_right_bmp.width);
			var th:Number=_h-(_top_bmp.height+_bottom_bmp.height);
			//上
			_top_bmp.width=tw;
			//下
			_bottom_bmp.width=tw;
			//左
			_left_bmp.height=th;
			//右
			_right_bmp.height=th;
			
			_center_bmp.width=tw;
			_center_bmp.height=th;
		}
		
//		private function drawRect(c:uint,rect:Rectangle):void
//		{
			graphics.beginFill(c);
			graphics.drawRect(rect.x,rect.y,rect.width,rect.height);
//			graphics.lineStyle(1,c);
//			graphics.moveTo(rect.x,rect.y);
//			graphics.lineTo(rect.width,rect.y);
//			graphics.lineTo(rect.width,rect.height);
//			graphics.lineTo(rect.x,rect.height);
//			graphics.lineTo(rect.x,rect.y);
			graphics.endFill();
//		}
		
		private function cutBmd():void
		{
			var rect:Rectangle;
			
			//1、左上
			rect=new Rectangle(0,0,_s9d.x,_s9d.y);
			var top_left_bmd:BitmapData=new BitmapData(rect.width,rect.height,true,0);
			top_left_bmd.copyPixels(_bmd,rect,despoint);
			_top_left_bmp=new Bitmap(top_left_bmd);
			addChild(_top_left_bmp);
//			drawRect(0xff0000,rect);
			
			//2、上
			rect.x=_s9d.x;
			rect.y=0;
			rect.width=_s9d.width;
			rect.height=_s9d.y;
			var top_bmd:BitmapData=new BitmapData(rect.width,rect.height,true,0);
			top_bmd.copyPixels(_bmd,rect,despoint);
			_top_bmp=new Bitmap(top_bmd);
			addChild(_top_bmp);
//			drawRect(0xffff00,rect);
			
			//3、右上
			rect.x=_s9d.right;
			rect.y=0;
			rect.width=_bmd.width-_s9d.right;
			rect.height=_s9d.y;
			var top_right_bmd:BitmapData=new BitmapData(rect.width,rect.height,true,0);
			top_right_bmd.copyPixels(_bmd,rect,despoint);
			_top_right_bmp=new Bitmap(top_right_bmd);
			addChild(_top_right_bmp);
//			drawRect(0xffffff,rect);
			
			//4、右
			rect.x=_s9d.right;
			rect.y=_s9d.y;
			rect.width=_bmd.width-_s9d.right;
			rect.height=_s9d.height;
			var right_bmd:BitmapData=new BitmapData(rect.width,rect.height,true,0);
			right_bmd.copyPixels(_bmd,rect,despoint);
			_right_bmp=new Bitmap(right_bmd);
			addChild(_right_bmp);
//			drawRect(0x00ff00,rect);
			
			//5、右下
			rect.x=_s9d.right;
			rect.y=_s9d.bottom;
			rect.width=_bmd.width-_s9d.right;
			rect.height=_bmd.height-_s9d.bottom;
			var bottom_right_bmd:BitmapData=new BitmapData(rect.width,rect.height,true,0);
			bottom_right_bmd.copyPixels(_bmd,rect,despoint);
			_bottom_right_bmp=new Bitmap(bottom_right_bmd);
			addChild(_bottom_right_bmp);
//			drawRect(0x0000ff,rect);
			
			//6、下
			rect.x=_s9d.x;
			rect.y=_s9d.bottom;
			rect.width=_s9d.width;
			rect.height=_bmd.height-_s9d.bottom;
			var botton_bmd:BitmapData=new BitmapData(rect.width,rect.height,true,0);
			botton_bmd.copyPixels(_bmd,rect,despoint);
			_bottom_bmp=new Bitmap(botton_bmd);
			addChild(_bottom_bmp);
//			drawRect(0x00ffff,rect);
			
			//7、左下
			rect.x=0;
			rect.y=_s9d.bottom;
			rect.width=_s9d.x;
			rect.height=_bmd.height-_s9d.bottom;
			var botton_left_bmd:BitmapData=new BitmapData(rect.width,rect.height,true,0);
			botton_left_bmd.copyPixels(_bmd,rect,despoint);
			_botton_left_bmp=new Bitmap(botton_left_bmd);
			addChild(_botton_left_bmp);
//			drawRect(0xeeeeee,rect);
			
			//8、左
			rect.x=0;
			rect.y=_s9d.y;
			rect.width=_s9d.x;
			rect.height=_s9d.height;
			var left_bmd:BitmapData=new BitmapData(rect.width,rect.height,true,0);
			left_bmd.copyPixels(_bmd,rect,despoint);
			_left_bmp=new Bitmap(left_bmd);
			addChild(_left_bmp);
//			drawRect(0x222222,rect);
			
			//9、中
			var center_bmd:BitmapData=new BitmapData(_s9d.width,_s9d.height,true,0);
			center_bmd.copyPixels(_bmd,_s9d,despoint);
			_center_bmp=new Bitmap(center_bmd);
			addChild(_center_bmp);
//			drawRect(0x99ff55,_s9d);
		}
		
		private function checkS9d(s9d:Rectangle):void
		{
			s9d.x=Math.floor(s9d.x);
			s9d.y=Math.floor(s9d.y);
			s9d.width=Math.ceil(s9d.width);
			s9d.height=Math.ceil(s9d.height);
			
			var error:Boolean=false;
			var errorMsg:String='';
			if(s9d.x<1)
			{
				error=true;
				errorMsg+='s9d.x<1';
			}
			if(s9d.y<1)
			{
				error=true;
				errorMsg+='s9d.y<1';
			}
			if((s9d.x+s9d.width)>(bmd.width-1))
			{
				error=true;
				errorMsg+='(s9d.x+s9d.width)>(bmd.width-1)';
			}
			if((s9d.y+s9d.height)>(bmd.height-1))
			{
				error=true;
				errorMsg+='(s9d.y+s9d.height)>(bmd.height-1)';
			}
			if(error)
				throw new Error("s9d error!!!:\n"+errorMsg);
		}
	}
}

天地会贴：

http://bbs.9ria.com/thread-147571-1-1.html